Connector with secondary locking and coupling mechanism

ABSTRACT

A connector assembly having a secondary locking member and a slide coupling member includes interengaging features between the slide coupling member and secondary locking member whereby the slide coupling member cannot be activated unless the secondary locking member is in its fully locked position and the secondary locking member further comprises extensions extending beyond a terminal receiving end wall of the connector housing to enable the secondary locking member to be manually depressed from the fully locked to the preassembly position so that it is particularly simple to repair the connector, for example when removal and reinsertion of terminals is required.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an electrical connector having a secondarylocking mechanism for locking terminals within cavities of theconnector.

2. Summary of the Prior Art

Such a connector is described in U.S. Pat. No. 4,944,688. The connectordisclosed therein includes a secondary locking member which is slideablealong the connector housing form a pre-assembly position to a fullylocked position. The secondary locking element does have keyingplatforms and integral latches to fix it to the main housing.

An electrical connector having a secondary locking mechanism and furthercomprising a coupling member for assisting coupling of the connector toa complementary connector is described in European Patent 726 617. Theconnector disclosed therein has an insulative housing with a pluralityof electrical terminals mounted therein and locked with first (primary)retention means such as resilient locking lances of the housing engagingin cavities of the terminals, the housing further provided with asecondary locking member that allows assembly of the terminals withinthe housing when in a preassembly position. The secondary locking memberis movable to a locked position to secure the terminals in the housingswith secondary locking means. The connector is further provided with acamming slide that engages with complementary members of a matingconnector for coupling the connectors together. The coupling memberreduces the forces required for mating. The coupling member furthercooperates with the secondary locking member such that it is not movableuntil the secondary locking member is in the fully locked position. Thisensures that connectors cannot be coupled unless the terminals arecorrectly mounted within their respective cavities and securely lockedwith primary secondary locking means. A particularly reliable connectionassembly is thus provided. A further advantage is that the camming slidecannot be moved to the wrong position during handling and transport, asit is blocked by the secondary locking member prior to complete assemblyof terminals within the connector.

One of the problems of the problems of the above described connectorsystem, which is also a problem of many other connectors with secondarylocking members with or without camming slides, is that once thesecondary locking member has been pushed to the fully locked position itis difficult to disengage. In particular, it is typical that specialtooling is required to move the secondary locking member from the fullylocked to the preassembly position. Once the secondary locking member isin the fully locked position it is desirable that it cannot be easilydisengaged as this may reduce the reliability of the connection assemblyif this could occur accidentally. The use of a special tool however maylead to damage of the connector if it is not correctly utilized by atechnician, and furthermore increases the costs of repair or maintenanceof the connection system.

It would be desirable to reduce the maintenance and repair costs of aconnection assembly, without reducing its reliability. It would also beparticularly advantageous to combine such effects into a connectionassembly as described in European Patent 726 617.

SUMMARY OF THE INVENTION

It is an object of this invention to provide an improved electricalconnector with secondary locking means. It would be particularlyadvantageous to provide such connector with a coupling assist mechanismcooperating with the secondary locking mechanism such as described in EP726 617.

Objects of this invention have been achieved by providing the connectorassembly according to claim 1. Disclosed is an electrical connectorcomprising a housing and electrical terminals mounted therein, asecondary locking member mountable to the housing in a first preassemblyposition where the terminals can be inserted and locked into theircorresponding cavities, the secondary locking member movable to a fullylocked position to securely lock the terminals in their cavities withsecondary locking means, the connector further comprising a couplingassist mechanism for assisting coupling with a mating connector, thecoupling assist member and secondary locking member interengaging whenthe secondary locking member is in a preassembly position to preventmovement of the coupling assist member, wherein the secondary lockingmember comprises a release projection extending through a wall of theconnector when the secondary locking member is in the fully lockedposition the release projection being manually engagable for displacingthe secondary locking member from the fully locked to the preassemblyposition. Advantageously therefore, the secondary locking member can beeasily released to the preassembly position for cost-effectivemaintenance of the connector.

The connector may advantageously comprise complementary shoulders on thesecondary locking and coupling assist member that engage once thesecondary locking member is in the fully locked position and thecoupling assist mechanism is moved from its preassembly position, theshoulders engaging such that the secondary locking mechanism cannot bemoved from the fully locked to the preassembly position once thecoupling assist mechanism has been displaced out of its preassemblyposition. The latter ensures that a particularly reliable electricalconnection is provided whereby the secondary locking mechanism cannot beunlocked during coupling with a complementary connector or thereafter.The latter also ensure that the coupling assist mechanism is moved tothe preassembly position prior to unlocking of the secondary lockingmember.

The secondary locking member release projections may be provided asprojections extending in a direction of coupling of the connectorsbeyond an end wall at a terminal receiving end of the connector housing.The projections may be provided extending adjacent a terminal receivingportion of the housing extending beyond the terminal receiving end suchthat they do not extend substantially beyond an end face of the housingin order to prevent accidental release.

Further advantageous aspects of this invention are described in theclaims or will be apparent from the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of an embodiment of this invention withsecondary locking and slide-lock coupling members exploded away;

FIG. 2 is a cross-sectional view through the connector with theslide-lock coupling member in a fully locked position and the secondarylocking member in a preassembled position;

FIG. 3 is a cross-sectional view through lines 3--3 of FIG. 2;

FIG. 4 is a similar view to that of FIG. 2, but with the slide-lockmember in a fully open position and the secondary locking member in afully locked position;

FIG. 5 is a cross-sectional view through lines 5--5 of FIG. 4;

FIG. 6 is an isometric view of an embodiment of this invention withsecondary locking and slide lock coupling members viewing in a directiontowards a terminal receiving end, where the secondary locking member isin the preassembly position;

FIG. 7 is a view similar to FIG. 6 with the secondary locking member inthe fully locked position;

FIG. 8 is a side view of the embodiment of FIGS. 6 and 7, with partialcross-sections, where the secondary locking member is in the fullylocked position;

FIG. 9 is a detailed view of the latching means between the secondarylocking member and the housing;

FIG. 10 is a view similar to FIG. 8 with the secondary locking member inthe preassembly position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, an electrical connector 2 comprises an insulativehousing 4 having cavities 6 for receiving electrical terminals therein,a secondary locking member 8 and a slide-lock coupling member 10.

Referring to FIGS. 1-3, the housing 4 extends between a mating face 12and a terminal receiving face 14, the housing having a terminalreceiving section 17 which is surrounded by a shroud 18 and separatedtherefrom by a cavity section 20 within which the secondary lockingmember 8 and arms 22 of the slide-lock coupling member 10 are received.The housing terminal section 17 comprises resilient locking lances 24integrally moulded therewith, the locking lances 24 in the shape ofcantilever beams and having locking protrusions 26 proximate their freeends that project into the terminal receiving cavities 16. Electricalterminals can be inserted into the cavities 16 whereby passage of theterminals past the locking lance protrusions 26 causes resilient outwardbiasing of the locking lances until engagement of the protrusions 26behind shoulders of the terminals to prevent removal of the terminalsfrom their corresponding cavities 16 towards the terminal receiving end14. Adjacent locking lances 24',24" of adjacent cavities 16',16" areseparated by a slot 28 to allow outward biasing of the lances duringmounting of the electrical terminals within their correspondingcavities.

The secondary locking member 8 comprises a mating end wall 30 andextending therefrom a shroud 32 that fits over the mating end of thehousing terminal receiving section 16. Also extending from the matingend wall 30 are short wall portions 34,36 that are positioned adjacentouter surfaces 38 of the locking lances 24 when the secondary lockinghousing 8 is in the fully locked position with respect to the housing 4as shown in FIG. 4. The wall portions 34,36 thus prevent outward biasingof the locking lances 24,24',24" in order to securely lock the terminalsthat have been inserted into the cavity 16 and that have engaged withthe locking protrusions 26 of the locking lances 24. In FIGS. 2 and 10,the secondary locking housing 8 is shown in the preassembly positionwhereby the wall portions 34,36 are disengaged from the locking lancesouter surfaces 38 such that the locking lances are free to biasoutwardly for reception of terminals within the cavity 16. The secondarylocking housing is held in the preassembly position by a latching means33' shown in FIG. 10 which maintains the member 8 in the preassemblyposition, the secondary locking member however being depressable underapplication of a certain force for snapping into the fully lockedposition as shown in FIGS. 4 and 8-9 where the latch means 33 securelyhold the secondary locking member in this position. The latching means33,33' comprises a resilient cantilever beam latch 35 integral with thesecondary locking member extending from a mating end 31 of the secondarylocking member to a free end 37 provided with a latch shoulder 39 thatengages a corresponding preassembly latching protrusion 41' or lockinglatching protrusion 41 projecting from an end wall of the housing 4. Thelocking protrusion 41 is provided with an oblique locking shoulder 47that enables disconnection of the secondary locking member from thefully locked position to the preassembly position. In other words, whenthe secondary locking member is pushed from the fully locked to thepreassembly position the oblique locking shoulder 45 allows the latchfree end 37 to resiliently outwardly bias and pass over the lockingprotrusion 41. The preassembly protrusion 41' is provided on the housingfor engaging with the latch 35 of the secondary locking member in thepreassembly position in a secure manner. The secondary locking membercannot be removed from the housing without special tools.

The secondary locking member 8 further comprises locking arms 42attached to a lower portion 40 of the shroud 32.

Referring to FIG. 1, the slide-lock coupling member 10 comprises aU-shaped body having a base wall 44 and side walls 46 extendinglaterally therefrom, the side walls 46 insertable through cutouts 48 inthe connector housing shroud 18 to slide adjacent an inner surface 49 ofthe shroud 18 (also see FIG. 5). The slide-lock coupling member sidewalls 46 comprise camming slots 50 that have a first longitudinalportion 52, extending from a complementary connector receiving end 54,the longitudinal portion 52 extending into an oblique portion 56 whichthen extends into a portion orthogonal to the longitudinal direction(where the longitudinal direction is the direction of coupling of theconnector 2 to a complementary connector). The camming slots 50 are forreceiving studs of a complementary connector (not shown), in order todraw the complementary connector towards the connector 2 when theslide-lock coupling member 10 is moved from the open position as shownin FIG. 5 to the closed position as shown in FIG. 3. The latter thuscauses coupling of the connector 2 to the complementary connector.Before sliding from the open to the closed position, the slide-lockcoupling member 10 receives the studs of the complementary connectorfirst into the longitudinal portion 52 of the camming slot 50, whichallows initial engagement of the connector to the complementaryconnector. If the slide-lock coupling member 10 is in the closedposition prior to coupling to the complementary connector, the studs ofthe complementary connector cannot enter into the camming slot lead-inportion 52 and simply abuts the complementary connector receiving end 54of the side walls 46, thus preventing coupling of the connectors. Theend portion 58 of the camming slots 50 is contiguous the complementaryconnector studs when the slide-lock coupling member 10 is in the fullyclosed position, and due to the orthogonal direction of the portion 58with respect to the coupling direction of the connectors, a forcetending to pull apart the connectors will not produce a force componentin the orthogonal direction and thus cannot open the slide-lock memberand release the connectors from the mating position.

The slide-lock member 10 further comprises a preassembly lockingshoulder 60 (see FIGS. 1 and 3) on the inner surface of the side walls46, against which latching protrusions 43 at ends 45 of the secondarylocking member locking arms 42 engage, when in the preassembly positionas shown in FIG. 3. During assembly of the terminals into the housingcavities 16, the secondary locking member 8 is in the preassemblyposition and the slide-lock member 10 is in the fully closed position asshown in FIG. 3, whereby the spring arm protrusions 43 engage with theshoulder 60. The slide-lock member 10 can thus not be moved into theopen position and can therefore not be coupled to a complementaryconnector.

It would also be possible to have an embodiment where the slide-lockmember is locked in the open position by engagement with the secondarylocking member to prevent coupling, rather than locked in the closedposition as shown in the embodiment of FIGS. 1-5.

Adjacent the shoulder 60 extends a recess 62 having a closed positionnotch 64 extending proximate the shoulder 60 and a preassembly positionnotch 66 proximate ends of the side walls 46 distant from the end wall44. Proximate the open position notch 66 is a retention shoulder 68 forengagement with the latching protrusions 43 to prevent removal of theslide-lock member 10 from the housing 4 as shown in FIG. 5. When thesecondary locking member 8 is moved from the preassembly position shownin FIG. 2 to its fully locked position shown in FIG. 4, the latchingprotrusion 43 disengages from the shoulder 60 and moves into therecessed area 62 to engage in the closed position notch 64. The notch 64engages with the latching protrusion 43 to provide a certain resistanceto moving the slide-lock member 10, but if sufficient force is appliedto the slide-lock member, it can be drawn to the open position as shownin FIG. 5 where the latch protrusion 43 engages in the open positionnotches 66 for provisionally holding the slide-lock member in the openposition. The connector 2 can thus be coupled to the complementaryconnector and the slide-lock member 10 is then depressed to the fullyclosed position, thereby drawing the connectors together and couplingthem. In the closed position, the slide-lock member 10 is latched with acertain force by engagement of the notches 64 with the spring beam latchprotrusions 43.

Once the slide lock member has been moved from its preassembly positionwhere it is locked by the latch protrusion 43 (where the slide lockmember may either be in the open or closed position depending on thechoice of the embodiment as described above), the secondary lockingmember 8 cannot be moved to the preassembly position. The latter occursby virtue of engagement of the latching protrusion 43 with an uppershoulder 70 as best seen in FIGS. 1 and 4, of the slide lock member 10.Therefore, once coupling of the connectors is permitted by movement ofthe secondary locking member to the locked position, and the slide lockmember 10 is displaced for example during coupling of mating connectors,it is no longer possible to accidentally displace the secondary lockingmember out of its fully locked position.

The secondary locking member 8 further comprises actuators 72 extendingfrom side walls thereof alongside a terminal receiving portion 74 of thehousing 4. The actuators 72 project through cavities 76 of a terminalreceiving end wall 78 opposed to the mating end 12 of the connector. Theterminal receiving end wall 78 is spaced at a certain distance from theoutermost terminal receiving end 14 of the housing, which defines theend of the terminal receiving portion 74 of the housing. When thesecondary locking member is in the fully locked position as shown inFIG. 4, the actuators 72 extend to a position proximate the terminalreceiving end 14 of the housing portion 74 such that they can bemanually activated (for example by hand) in order to displace thesecondary locking member back to its preassembly position as shown inFIG. 2. In the latter position, the extensions 72 may be positionedsubstantially at the end walls 78 or in the proximity thereof.

As mentioned previously, the secondary locking member 8 cannot beactivated until the slide lock member 10 is in its preassembly position,which may be the open or closed position depending on the chosenembodiment. Referring mainly to FIGS. 8-10, the secondary locking memberlatching features 35,37 that cooperate with the locking protrusion 41provides a certain resistance, in view of the oblique latching surface47 to displacement of the secondary locking member to the preassemblyposition. The protrusion 41' has a locking surface that is angledslightly to encourage the latch arm 45 to bias into a tighter lockingrelationship with the housing. In other words, the latch can be pushedfrom the fully locked to the preassembly position but not released fromthe connector housing unless special tooling is used.

As the actuator 72 extends alongside and is proximate or may even be ina contiguous relationship with side walls 75 of the terminal receivingportion 74, they are protected from damage and inadvertent actuationthereof even when in the fully locked position as shown in FIG. 4. Aperson can however easily access the actuator 72 with their fingers. Theactuator 72 also provides a clear visual indication of the secondarylocking member being in its fully locked position.

What is claimed is:
 1. An electrical connector comprising a housing forreceiving electrical terminals therein, and a secondary locking membermountable to the housing in a first preassembly position where theterminals can be inserted and locked in corresponding cavities, thesecondary locking member movable to a fully locked position to securelylock the terminals in their corresponding cavities, the housingextending from a mating end that faces a complementary connector to bemated with the connector, to a terminal receiving end where theterminals are inserted into the cavities of the housing, the housingincluding an end wall located towards the terminal receiving end, thesecondary locking member being mountable to the housing from the matingend, wherein the secondary locking member includes at least one actuatorthat projects through a cavity in the end wall when the secondarylocking member is in the fully locked position, such that the actuatorcan be manually activated to move the secondary locking member from thefully locked to the preassembly position.
 2. The connector of claim 1wherein the secondary locking member and connector housing are providedwith a pair of cooperating latching means, a first latching meanssecuring the secondary locking member to the housing in the preassemblyposition such that the secondary locking member cannot be removedmanually from the housing, and a second latching means that includes alatching protrusion having an oblique latching surface engagable by acomplementary resilient latching member when the secondary lockingmember is in a fully locked position such that upon application of areleasing force on the actuator the resilient latches are biased overthe latching protrusion.
 3. The connector of claim 1 wherein a terminalreceiving portion of the housing, within which the cavities are providedfor receiving the terminals, extends beyond the end wall to the terminalreceiving end, the actuator extending proximate and alongside theterminal receiving portion.
 4. The connector of claim 3 wherein theactuator extends beyond the end wall when the secondary locking memberis in the fully locked position.
 5. The connector of claim 3 wherein thesecondary locking member actuator is substantially within the connectorhousing when the secondary locking member is in the preassemblyposition.
 6. The electrical connector of claim 1 wherein the connectorfurther has a coupling assist member for assisting mating with thecomplementary connector, the coupling assist member and secondarylocking member interengaging when the secondary locking member is in apreassembly position to prevent movement of the coupling assist member.7. The connector of claim 6 wherein the coupling assist member comprisesa locking shoulder which engages with a complementary locking arm of thesecondary locking member when the secondary locking member is in thefully locked position and the coupling assist member is displaced fromits preassembly position, such that the secondary locking member isprevented from displacement to the preassembly position.
 8. Theconnector of claim 6 wherein the coupling assist member comprises aU-shaped body having a base wall and side walls extending laterallytherefrom, the side walls are insertable through cutouts in a connectorhousing shroud to slide adjacent an inner surface thereof, the couplingmember side walls having camming slots for receiving complementary studsof the complementary connector.